How to tell if the laser is working like it should

It seems like over time my laser is not working as well as when I first got it. I now have trouble cutting hard wood that is 1.5 to 2 mm thick.

Is there some kind of test to see if the laser is still 10 watts. The glass is clean, it is focused correctly and I also use air assist, but on some wood it can take 20 passes at 100% and 450 speed. Doing this it burns the wood badly on the top side.

Starting to think there is a problem because this machine has less than 10 hours on it. Any help will be greatly appreciated.

There is a “laser” group you could have posted this too instead of a general one.
But to help with your problem, your diode laser( guessing since you didn’t state but said 10W ) could be worn out. Sure it might only have 10 hours on it but if it’s been run at 100% for most of that time it’s probbably helped weaken the diode. Also, if there is not good heat sink air flow that will weaken the diode. If the cooliing is not continued for a period after the diode stopped lasing that residual heating could weaken the diode.

When you say the “glass is clean” do you mean the focusing lens? Have you run a ramp test to be sure you have the focus correctly set?

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I’ve moved it to the the laser group. :smiley:

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Thank you. I have an XTool D1 10w diode laser. I do run it close to 100% most of the time, but I overestimated how many hours I really have on the unit. If it is based on how long the laser is actively burning something it might only be 3 hours.
When you say the “glass is clean” do you mean the focusing lens?
Yes, and I have not run a ramp test, not sure what that is. Lastly the D1 has a fold down focusing feature so if used, it should always be in focus.

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Laser diodes do lose power with use, hard to quantify but I’ve noticed it on both my 5 and 40w modules. And there is no real fix. :pleading_face:

If you want some really nerdy discussion of this look at Blu-Ray player forums. Blue light laser diodes are used there too, and older players fail as the diodes fail.

Heat kills diodes.

Higher temperatures kill them faster.

Higher power means more heat.

More heat without better cooling means short lifetime.

(Example: My “60-watt equivalent” original Philips LED light bulbs (the ones with three yellow plastic covers that glow white) lasted a year or two. The “40-watt equivalent” versions purchased at the same time or earlier are still going strong after 15 years of daily use for most of the day. They have similar overall design.)

I would expect short lifetime to be a likely design defect for high power LED lasers that is still the manufacturer’s fault but an unsurprising type of design defect. :cry:

…and even small transients can damage these diodes.

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good resource here:

It specifically talks about laser diode lifetimes when you scroll down.

I think laser module makers generally do a good job with the thermal bond between the dode heatsink and module heatsink, the units would fail instantly if they scrimp on this.

But, of course, they tend to drive the diodes at their maximum current, and they do not use active cooling (at least, not in our price bracket). The diode itself and the thermal shocks within it are the major factor for lifetime, which I guess can be supplier dependant.

Unless the thermal bond in a module is weak, or the diode is being over-driven, there is no ‘Defect’ per sey; just a classic price / performance / lifetime compromise.

The real take away is that the diode will dim with time, but you can maximize it’s life by lowering it’s maximum power. Which is advice I often see given for tube lasers here too :innocent:

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Do you have air assist? It really helps with both cutting performance, and reducing the flashing and charring around the cut.

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Ten hours didn’t fit within what I would call a reasonable engineering compromise. If that’s heat damage, they didn’t do their engineering right, either in design or execution…